Remotely controlled and electronically operated variable-pitch sailboat propeller

ABSTRACT

Embodiments of the present invention may provide a propeller system for propelling a vessel. The propeller system may comprise a propeller body operable to connect to a drive shaft of the vessel; a propeller shaft extending out of the propeller body, the propeller shaft operable to be driven by the drive shaft and further operable to rotate about its longitudinal axis, wherein if the propeller shaft is in a first position within the propeller body, the propeller shaft is rotatable about its longitudinal axis only when torque transmitted from the drive shaft causes the propeller shaft to rotate; a propeller blade disposed outside of the propeller body and connected to the propeller shaft, the propeller blade operable to rotate according to the propeller shaft; and a radio receiver situated within the propeller body operable to receive a signal, that, upon receiving the signal, is further operable to allow the propeller shaft to move from the first position to a second position within the propeller body, thereby allowing the propeller blade to freely rotate according to water currents that cause the propeller blade to rotate to a position that minimizes drag of the propeller blade against the water currents.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 61/153,536, filed Feb. 18, 2009.

BACKGROUND OF THE INVENTION

The present invention generally relates to a remotely controlled and electronically operated variable-pitch sailboat propeller, and more specifically relates to a remotely controlled electronically operated variable-pitch sailboat propeller that may be controlled wirelessly via a remote control to change the position of components within the propeller.

Currently, a sailboat may include a propeller that may be used alone or in conjunction with wind, captured by one or more sails on the sailboat, in order to propel the sailboat. When the propeller is not in operation, so that the sailboat is propelled by the wind captured by the one or more sails on the sail boat, it may be generally desirable for the out-of-operation propeller to be situated as to have as little drag as possible in order to prevent the propeller from hindering the movement of the sailboat as it is propelled by the wind.

However, if a propeller on a sailboat is designed to be situated so that it produces as little drag as possible when it is not used to propel the sailboat, such a propeller design may not produce as much thrust as may be necessary in order to propel the sailboat in an efficient manner when the propeller is used to propel the sailboat.

As can be seen, there is a need for a propeller on a sailboat that produces little drag when not in use while still providing enough thrust to efficiently propel the sailboat when the propeller is in use.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a propeller system for a vessel may comprise a propeller body operable to connect to a drive shaft of the vessel; a propeller shaft extending out of the propeller body, the propeller shaft operable to be driven by the drive shaft and further operable to rotate about its longitudinal axis, wherein if the propeller shaft is in a first position within the propeller body, the propeller shaft is rotatable about its longitudinal axis only when torque transmitted from the drive shaft causes the propeller shaft to rotate; a propeller blade disposed outside of the propeller body and connected to the propeller shaft, the propeller blade operable to rotate according to the propeller shaft; and a radio receiver situated within the propeller body operable to receive a signal, that, upon receiving the signal, is further operable to allow the propeller shaft to move from the first position to a second position within the propeller body, thereby allowing the propeller blade to freely rotate according to water currents that cause the propeller blade to rotate to a position that minimizes drag of the propeller blade against the water currents.

In another aspect of the present invention, a method for controlling a propeller system may comprise transmitting a first signal, the first signal causing torque to be transmitted through a drive shaft to a propeller shaft in a first position, thereby causing the propeller shaft and a propeller blade attached to the propeller shaft to rotate according to the torque transmitted through the drive shaft; and wirelessly transmitting a second signal, the second signal causing the propeller shaft from a first position to a second position, thereby allowing the propeller blade to freely rotate according to water currents that cause the propeller blade to rotate to a position that minimizes drag of the propeller blade against the water currents.

In another aspect of the present invention, a method of operating a propeller system may comprise receiving a signal by a radio receiver; in response to receiving the signal, moving a propeller shaft from a first position to a second position; and allowing a propeller blade connected to the propeller shaft at the second position to freely rotate according to currents encountered by the propeller blade, thereby minimizing drag of the propeller blade against the currents.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross-sectional overhead view of a sailboat propeller in accordance with an embodiment of the invention; and

FIG. 2 shows a cross-sectional side view of the sailboat propeller of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.

Various inventive features are described below that can each be used independently of one another or in combination with other features.

Broadly, embodiments of the present invention generally provide a remotely controlled and electronically operated variable-pitch sailboat propeller that may be controlled wirelessly via a remote control to change the position of components within the propeller.

By using a remote control that communicates wirelessly with a radio receiver/transceiver on a propeller, an operator may send commands to the propeller via the radio remote control anytime the operator wishes to change the operation of the propeller, such as changing the position of components within the propeller. The propeller may react to signals received from the remote control to move components of the propeller, such as propeller blades, to a position in accordance with the signals sent by the remote control and received by the radio receiver/transceiver.

Thus, the operator may be able to choose when and how to communicate with the propeller in order to change the position of components within the propeller, so that the propeller may not need to include bulky mechanical linkages that may otherwise be needed in order for an operator to communicate with and control the propeller.

Referring to FIGS. 1 and 2, a sailboat propeller 100 comprise blade locking cam 101, solenoid 102, radio receiver/transceiver 103, battery/power source 104, propeller root 105, propeller main body 107, aft locking cap 108 with pitch adjusting screw 108 a, spring 109, cartridge body 110, locking nut 111, bearing 112, and seal 113. The propeller 100 may attach to a propeller drive shaft 106 of a sailboat in order to propel the sailboat.

The blade locking cam 101 may be a thin, hardened, steel washer-like device with a machined slot 101 a that may be angled to allow locking pins 102 a on the solenoid 102 to move forward and back for slight variations in pitch. The blade locking cam 101 may also be secured to the propeller root 105 so that the blade locking cam 101 moves in concert with the propeller root 105 as the propeller root 105 turns along its longitudinal axis and may act to prevent the propeller root 105 from sliding back out of the bearing 112. When the locking pins 102 a are positioned so that they rest within the machined slot 101 a, propeller blades 105 a may be locked at a desired pitch. The blade locking cam 101 may slide onto the bottom of the propeller root 105 and may be secured in place against the bearing 112 by the locking nut 111, thus securing the propeller root 105 to the propeller main body 107.

The solenoid 102 may be magnetic and may be a copper-wound spring with locking pins 102 a at either side. When energized, the copper-wound spring may produce a magnetic field that pull the locking pins 102 a inward, thus releasing the blade locking cam 101 and thereby allowing the propeller blades 105 a to swing into a neutral position, meaning that the propeller blades 105 a are not locked into position and may therefore swing freely.

The radio receiver/transceiver 103 may be a commonly manufactured radio receiver/transceiver of any design that may receive a signal of short duration from a radio transmitter, such as a remote control. Upon receiving the signal, the radio receiver/transceiver may allow a small electric charge to be released to the solenoid 102, thereby causing the blade locking cam 101 to be released to allow the propeller blades 105 a to swing into a neutral position.

The battery/power source 104 may be direct current energy or a charged storage device that may be configured to provide power to the radio receiver/transceiver 103. The battery/power source 104 may be any battery or battery cell, including but not limited to general purpose batteries, lithium ion batteries, nickel cadmium batteries, nickel metal hydride batteries, lead acid batteries, deep cycle batteries, rechargeable batteries, or any other power sources including but not limited to fuel cells and capacitors. The voltage of the battery/power source may be but is not limited to 1-24 volts, and more specifically may be 3-12 volts.

The propeller root 105 may work to propel a sailboat attached to the propeller, and may be a combination of a propeller blade 105 a and a machined shaft 105 b that may slide into the propeller main body 107 through the seal 113 and two sets of bearings 112. The propeller 100 may comprise two or more propeller blades 105 a. The bearing 112 may be a roller bearing that is pressed into the propeller main body 107 to support the propeller root 105 within the propeller main body 107. The seal 113 may be a press-in watertight seal that may be pressed over the bearings 112 to keep water out. The propeller root 105 may be made of a non-ferrous material such as brass or aluminum, but may not be limited to any particular material, such as metal. In an exemplary embodiment, the propeller root 105 may be made of plastic, resins, or any other hard and durable material.

The propeller main body 107 may be a casing for the components of the propeller 100 and may be the means by which the propeller 100 is attached to the drive shaft 106. The propeller may be made of a material that both resists corrosion and may be hard enough to withstand the stress encountered as the propeller 100 travels underwater. The propeller main body 107 may be made of brass or aluminum, but may also be made of any other suitable material. The propeller main body may be machined unit to allow other components of the propeller 100 to slide into their proper positions.

The aft locking cap 108 with pitch adjusting screw 108 a may be designed to close off a back access compartment 107 a of the propeller main body 107, thereby making the propeller main body 107 watertight. The aft locking cap 108 may be made of the same material as the propeller main body 107 and may screw into the propeller main body 107 via a the pitch adjusting screw 108 a. The pitch adjusting screw 108 a may move in and out of an aft locking cap opening 108 b, so that when the pitch adjusting screw 108 a is screwed in and out the pitch adjusting screw 108 a may push the cartridge body 110 forwards and back, thereby turning on the propeller 100 when the pitch adjusting screw 108 a is screwed into the aft locking cap 108. The spring 109 may act to push the cartridge body 110 back against the aft locking cap pitch adjusting screw 108 a. The cartridge body 110 may be made of plastic and may house the battery/power source 104, the radio receiver/transceiver 103, and the solenoid 102.

The propeller 100 of a sailboat may be controlled by the drive shaft 106 and a radio remote control. When the locking pins 102 a rest inside the machined slot 101 a of the blade locking cam 101, the propeller blades 105 a may be in a locked position, so that when power is sent to the drive shaft 106, such as by starting the sailboat's engine, putting the sailboat into a forward gear, and pressing an accelerator pedal, the torque of the drive shaft 106 causes the propeller root 105 and the propeller blades 105 a to rotate according to the torque of the drive shaft 106, thus propelling the sailboat. If the accelerator pedal is lifted off, so that no torque is transferred through the drive shaft 106, the propeller root 105 and propeller blades 105 a may be locked into position so that they remain in a fixed position. When the propeller blades 105 a are locked into the fixed position, so that the propeller blades 105 a are substantially vertical, the propeller blades 105 a may not be moveable by water currents flowing past the propeller blades 105 a, thereby causing additional drag to the sailboat as it flows through the water.

When the radio remote control is manipulated, such as by pressing a button on the radio remote control, a signal may be sent from the radio remote control to the radio receiver/transceiver 103. Upon the radio receiver/transceiver 103 receiving the signal sent from the radio remote control, the radio receiver/transceiver 103 may send a small electrical charge to the solenoid 102, thereby causing the locking pins 102 a on the solenoid 102 to retract from the machined slot 101 a and unlocking the blade locking cam 101 connected to the propeller root 105 so that the propeller blades 105 a may now swing freely. Water currents flowing past the propeller blades 105 a as the propeller 100 travels through water may then naturally push and turn the propeller blades 105 a to a position, such as a substantially horizontal position, that minimizes the drag from propeller blades 105 a as the sailboat travels through water.

To lock the propeller blades 105 a so that the propeller 100 may be used to propel the sailboat, power may be sent to the drive shaft 106, such as by pressing an accelerator pedal on the sailboat. The powered drive shaft 106 may then cause the propeller root 105 and the propeller blades 105 a to rotate. As the propeller root 105 rotates, the blade locking cam 101 connected to the propeller root 105 may also rotate, so that the blade locking cam 101 may press the locking pins 102 a inward until the machined slot 101 a of the blade locking cam 101 is lined up with the locking pins 102 a. Because the blade locking cam 101 may no longer be pressing against the locking pins 102 a when the machined slot 101 a is lined up with the locking pins 102 a, the locking pins 102 a may pop back up and rest within the machined slot 101 a, thus locking the blade locking cam 101, the propeller root 105, and the propeller blades 105 a to the propeller and thereby allowing the propeller blades 105 a to rotate and propel the sailboat as the drive shaft 106 drives the propeller root 105.

It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. 

1. A propeller system for a vessel, comprising: a propeller body operable to connect to a drive shaft of the vessel; a propeller shaft extending out of the propeller body, the propeller shaft operable to be driven by the drive shaft and further operable to rotate about its longitudinal axis, wherein if the propeller shaft is in a first position within the propeller body, the propeller shaft is rotatable about its longitudinal axis only when torque transmitted from the drive shaft causes the propeller shaft to rotate; a propeller blade disposed outside of the propeller body and connected to the propeller shaft, the propeller blade operable to rotate according to the propeller shaft; and a radio receiver situated within the propeller body operable to receive a signal, that, upon receiving the signal, is further operable to allow the propeller shaft to move from the first position to a second position within the propeller body, thereby allowing the propeller blade to freely rotate according to water currents that cause the propeller blade to rotate to a position that minimizes drag of the propeller blade against the water currents.
 2. The propeller system of claim 1, further comprising: a locking pin operable to lock the propeller shaft in the first position;
 3. The propeller system of claim 2, further comprising: a blade locking cam connected to the propeller shaft, the blade locking cam including a slot operable to receive the locking pin, wherein the propeller shaft is in the first position if the locking pin rests within the slot, and wherein the propeller shaft is in the second position if the locking pin does not rest within the slot.
 4. The propeller system of claim 3, further comprising: a magnetic solenoid situated within the propeller body and connected to the locking pin, wherein upon the radio receiver receiving the signal, the radio receiver is operable to send a charge to the magnetic solenoid, thereby contracting the magnetic solenoid and causing the locking pin to no longer rest within the slot, and further causing the propeller shaft to move from the first position to the second position.
 5. The propeller system of claim 4, wherein: wherein upon receiving torque from the drive shaft while the propeller shaft is at the second position, the blade locking cam is operable to move until the locking pin is inserted into and resting within the slot, thereby moving the propeller shaft from the second position to the first position.
 6. The propeller system of claim 1, further comprising a power source configured to provide power to the radio receiver.
 7. The propeller system of claim 1, further comprising a remote control operable to wirelessly send the signal to the radio receiver.
 8. A method for controlling a propeller system, comprising: transmitting a first signal, the first signal causing torque to be transmitted through a drive shaft to a propeller shaft in a first position, thereby causing the propeller shaft and a propeller blade attached to the propeller shaft to rotate according to the torque transmitted through the drive shaft; and wirelessly transmitting a second signal, the second signal causing the propeller shaft from a first position to a second position, thereby allowing the propeller blade to freely rotate according to water currents that cause the propeller blade to rotate to a position that minimizes drag of the propeller blade against the water currents.
 9. The method of claim 8, further comprising: retransmitting the first signal if the propeller shaft is at the second position, thereby causing the propeller shaft to return from the second position to the first position.
 10. The method of claim 8, further comprising: wirelessly receiving the second signal at a radio receiver at the propeller system.
 11. The method of claim 10, further comprising: transmitting an electrical charge from the radio receiver to a magnetic solenoid, thereby causing the magnetic solenoid to contract and moving the propeller shaft from the first position to the second position; and in response to the transmitting of the electrical charge, contracting the magnetic solenoid, thereby causing locking pins attached to the magnetic solenoid to move out of a slot on a blade locking cam.
 12. The method of claim 8, further comprising: moving a blade locking cam so that slots on the blade locking cam move over locking pins attached to a magnetic solenoid in response to the propeller shaft rotating according to the torque.
 13. A method for operating a propeller system comprising: receiving a signal by a radio receiver; in response to receiving the signal, moving a propeller shaft from a first position to a second position; and allowing a propeller blade connected to the propeller shaft at the second position to freely rotate according to currents encountered by the propeller blade, thereby minimizing drag of the propeller blade against the currents.
 14. The method of claim 13, further comprising: receiving a torque from a drive shaft; and in response to receiving the torque, moving the propeller shaft from the second position to the first position, thereby allowing the propeller shaft to rotate according to the torque.
 15. The method of claim 13, further comprising: transmitting an electrical charge from the radio receiver to a magnetic solenoid, thereby causing the magnetic solenoid to shrink and moving the propeller shaft from the first position to the second position. 